The present invention relates to a bus controller for an electronic device which has an intelligence (or processor) of its own and a memory having a large management block of individually addressable memory locations which are connected to each other by a system bus, the bus controller being adapted to be connected at least to the memory and a network bus, the network bus networking several electronic devices with each other.
Such bus controllers are widely used. They are employed, for instance, in field buses such as the PROFIBUS. The PROFIBUS protocol describes, for instance, how individual requests to send and receive are to be handled towards the outside, i.e. on the network bus. However, it does not provide any suggestion as to how requests to send and receive can be effectively managed within the system.
U.S. Pat. No. 4,896,261 discloses an electronic device which has a bus driver which manages a send queue. The send queue is organized as a double-linked list. Only the list data as well as the pointers to the data blocks are stored in the pointer blocks. A similar disclosure is provided by U.S. Pat. No. 5,165,021.